Effects of temperature on the physicochemical properties and volatile profiles of 'Shine Muscat' grape during postharvest storage.

This study aimed to analyze the effects of temperature on physicochemical properties and volatile profiles of the 'Shine Muscat' grape during postharvest storage. Fresh grapes were stored at 4 °C and 25 °C for 28 d. The salable weight and appearance-related quality were better maintained in low-temperature storage (4 °C), and grapes stored at 25 °C presented a higher total soluble solids/titratable acidity ratio (TSS/TA), total phenols, total flavonoids, and total anthocyanins during storage compared to 4 °C. Furthermore, the grape at 4 °C exhibited more abundant volatiles and aroma series in the early storage stage. For long-term storage of more than 21 d, low-temperature storage (4 °C) enhanced the loss of total volatile content and increased the contents of some volatile compounds that might cause negative odor. Regardless of storage temperatures, 2-methyl-1-penten-3-one was identified as a potential substance for detecting fresh grapes. In conclusion, keeping the grapes at 4 °C is beneficial to prolong the storage period and obtain abundant flavor. Eating within 4 d for the grape stored at 4 °C is recommended. Meanwhile, a temperature of 25 °C is more beneficial to obtain more phenols and flavonoids.